1. Field of the Invention
This invention relates to the field of solid state electronics and particularly to solid state electronic logic circuits.
2. Description of the Prior Art
Prior art logic integrated circuits in silicon or germanium have utilized p-n diodes as the logic inputs to control the gate of an NPN bi-polar transistor. However, Schottky barrier diodes and field effect transistors (FETs) have not been used to construct such logic integrated circuits in silicon or germanium integrated circuits.
FETs have been used to construct logic integrated circuits in GaAs. In such prior circuits, GaAs FETs (rather than Schottky diodes) are used as the actual nonlinear logic elements. Because FETs are relatively large, these prior art GaAs circuits require considerable chip area. Further, FETs, unlike diodes, are three terminal devices and require additional area for overcrossings. While Schottky barrier diodes have been used in such prior circuits, they have not been used to perform the logic function. Rather, they have been used only for level shifting. Further, the Schottky barrier diodes previously used for level shifting have large areas (about 3.mu..times.20 to 40.mu.). Consequently, their capacitance is high and they do not provide the high speed and low current operation that is desirable in the actual non-linear logic elements.